Reversible variable capacity fluid pump



Feb. 17, 1953 w. H. DE LANCEY ErAL 2,628,567

REVERSIBLE VARIABLE CAPACITY FLUID PUMP Filed Dec. 12, 1946 2Sl-lEETS-Sl-IEET 1 .59 6Z v \Y bk 60 1 IN H Mrrm Hazing .l'dm'r: E W

17, 1953 w. HIDE LANCEY ETAL. 7

REVERSIBLE VARIABLE CAPACITY FLUID PUMP Filed Dec. 12, 1946 PatentedFeb. 17, 1953 2,628,567 REVERSIBLE VARIABLE CAPACITY FLUID PUMP Warren-H. De Laneey and Edwin E. Vincent,

Springfield, Mass assignors,

by-mesne a'ssignmerits, to Houdaille-Hershcy CorporatioznDetroit',Mich.,.a corporation of-Michigan l Application December 12, 1946, SerialNo.'715, 84 4 "13 Claims. (Cl. 103-120) This invention relates to avariable capacity fluid pump of the vane type, and more particularly tothat'type of variable capacity pump in which the displacementautomatically adjusts itself to compensate for variations in the drivingspeed or output requirements-the displacement being modulated frommaximum to zeroby comparatively slight increases of pressure afterreaching a predetermined point. That is, the volume of the pumps outputdecreases as the delivery pressure increases, so that the pump is notrequired to operate under any appreciable back pressure in periods ofzero output requirements.

A primary object of the present invention is to provide such a variablecapacity pump with component parts such that the' direction of the pumprotor may be reversed by merely altering the relative positions of theseparts thereby to permit the pump to be operated efficiently in either aclockwise or a counterclockwise direction depending upon the dispositionof these component parts.

Another object of the presentinvention is to provide such a variablecapacity pump with means whereby the fluid pressure produced by the pumpmaybe varied.

A further object of this invention is to simplify the construction ofpumps having the above noted capabilities to the'end that they maybemanufactured at a minimum expense.

With the above and other objects in view as will hereinafter-appear, theinvention comprises the devices, combinations and arrangements of partshereinafter set forth and illustrated in the accompanying drawings of apreferred embodiment of the invention from which the several features ofthe invention and the advantages attained thereby will be readilyunderstood by those skilled in the art.

In the accompanying drawings:

Fig. 1 represents a sectional view of a piunp incorporating the presentinvention, the section being taken transversely of the rotor shaft.

Fig. 2 represents a sectional view taken substantially along line 1-2 ofFig. 1.

Fig. 3 represents. a front view, in reduced scale, of the device asdisclosed in Fig. 1 with the component parts thereof so assembled as toenable the rotor shaft to rotate in a counterclockwise direction.

Fig. 4 represents a front view, in reduced scale, of the present deviceas disclosed in Fig. 1 with the component parts thereof assembled in amanner suchas to enable the rotor shaft thereof to rotate in a clockwisedirection.

Fig. 5 represents a face view of aport-containing disk.

:Fig. 6 represents a sectional view of theele- 2 ment disclosed in "Fig.S5 and taken substantially along the line 6-6 of Fig.5.

Fig. 7 illustrates "the real-end viewof "theelement disclosed in Fig."5.

Fig. 8 represents a sectional view of the element disclosed inFig. "7jand'taken substantially along "the line 8-'80f Fig. '7.

Like reference characters refer to like parts in the differentfigures.

Referring particularly to Figs. :1 and 2, the presentinventionis'inco'rporatedin a pumping unit which comprisesaghousing element IIIof, a generally annular form and "having an end plate ll securedoveroneend thereof'by means of a plurality of suitable bolts l2 whichpass through holes 13, provided in the end plate ll thus to bethreadeddirectly: into the housing Ill. The housing Ill isformed-with'a'central'bore 14 opening directly into a substantiallycylindrical chamber 15 whichis closed over byjmeans of the end plate II.

Rotatably journaled within the bore 14 'is a rotor shaft 16 which may bedriven in "any suitable manner, asbymeans of a driving gear, not shownherein, which'may'imesh with a .gear l1 keyed or otherwisesuitablysecured upon the distal end of the rotor shaft '15. The shaft.IB passes through the'chamberliand carries within'this chamber a pumprotor .l'8,the latter having an inner hub portion "which surroundssaidshaft and is keyedthereto' as shownat 20. The pump rotor is formed inthe usual manner with a series of radial slots 2!, in each of which isdisposed a radial slidable vane 22. The outer ends of said vanes'areadapted, according to this invention. to work against theinterior'periphery of a ring-like modulato'r'member '23 which surroundsthe rotor ill in the pumpspace provided by the cylindrical chamber 15 ofthe housing I'D, said member 23 as well as the-several vanes 22extending across said space from side to side, between opposed innerfaces 25 and 26 'of the housing I 0 and a port-containing member "27which will be hereinafter described.

Thering-like member on its outer periphery is appreciably smaller indiameter than the chamber of bore .l5,.and on its inner periphery isappreciably larger in 'diameterthan the pump rotor I 8, in consequence*ofthisthere is ample opportunity in the'pump space surrounding therotor l8 for'free movement of said member 2 3, into positions of varyingeccentricity relative to the rotor l8, to vary thepumping action 'ofthelatters slidable vanes 22,:22.

A simple and'highly advantageous mounting of member. 23,.for purposes ofsuch eccentricitymovements isobtained by providing on-theoutside surfaceof said member 23,.andpreferab1y across its entire width a rib 28 ofsubstantially triangular ,cross .1 section; and with side surfaces at anacute angle to each other so as to form at their intersection a virtualknife edge, as indicated at 29. For the reception of the rib 28 thesurface of bore 15, as shown in Fig. 2, is provided with a two-sideindentation or cleft 38, somewhat shallower than the rib 28 and with itsintersecting sides at an appreciably larger angle to each other than theintersecting sides of said rib, thus to give ample clearance for freeand frictionless rocking movements of the ring 23 on the axis affordedby the bottoming of the rib edge '29 in the angular indentation 30. Asimilar indentation or cleft 3| is formed in the bore I5 at a pointdiametrically opposite the indentation 38. By providing this secondindentation- 3| the ring 23 may be assembled into the pumping unit ineither of two positions thereby to permit, as hereinafter described, theshaft It to be rotated in either a clockwise or a counterclockwisedirection. Provided on the outside periphery of the modulator ring 23,at a point diametrically opposite the rib 29, is an arcuate boss 32which is adapted to engage the inner periphery of the bore I5 for thepurpose of maintaining the rib 28 within its proper indentation, whetherit be indentation 30 or 3!.

The ring 23 presents a continuous unbroken interior cylindrical surfaceto the ends of the vanes 22, 22 there being no .need to provide saidring with fluid openings to the spaces between the vanes since theingress of fluid to and its exit from said spaces is obtained laterallyby way of passages leading into the pumping spaces through theport-containing member 21.

Referring particularly to Figs. 1, 5, 6, '1, and 8, the forward end ofthe shaft 16 projects into a bore 33 provided axially of theport-containing member 21 which is snugly positioned within acylindrical recess 34 provided within the inner face of the end platell. Asherein shown, the member 21 provides a fluid intake passage 35 anda fluid delivery or offtake passage 36. Both of these passages 35 and 38communicate with the opposite face of the member 21 by means of conduits31 and 38 respectively. Formed on the inner face 26 of the member 21 arearcuately shaped fluid-conducting passages 39 and 40 which communicaterespectively with the conduits 31 and 38. As shown in Figs. 3 and 4, theelongated passageway 39 is disposed'in the fluid intake zone and theelongated passage 40 is disposed in the fluid delivery zone of the pathof travel of the vanes 22, .22. The function of these grooves isprincipally to insure an unrestricted internal flow of fluid as drawninto and expelled from the spaces between the vanes 22, 22 by therotation of the rotor 18 within the ring 23 in the directions of thearrows 4| and 42 associated with the Figs. 3 and 4 respectively.

The intake groove is preferably made wide enough to overlap the ring 23on both sides, thereby to give the enteringfluid access to the spacebetween said ring and the bore 15, and to reduce the fluids tendency tobecome aerated by reason of undue restriction of its flow. Furthermore,this-construction will permit the delivery of a small portion of thefluid to a conduit 43 disposed within thehousing ID for the purpose ofproviding a means whereby fluid may be delivered from the chamber l5 tothe outer periphery of the shaft I'Bthereby to lubricate the latterelement. This conduit also functions to prevent the pumping elementsfrom forcing fluid from the chamber l5 out of the casing [0 along theshaft [6.

As best shown in Fig. 1, the rotors inner hub portion I9 is of lesswidth, axially of-the shaft [6, than the vanes 22, 22, this reduction ofthe width resulting from the rotors opposite faces being formed withcircular recesses 44 and 45. Since these recesses 44 and 45 areintersected by the inner ends of the radial slots 2|, 2!, it followsthat the end extremities of the inner edges of the several vanes 22, 22are located in these face recesses 44 and 45 of the rotor I8. Alsolocated in such recesses 44 and 45 are loose rings 46 and 41,respectively, each encircling the shaft I6 and having an externaldiameter that gives it virtual peripheral contact with the inner edgeportion of each of the several vanes 22, 22 of the rotor. Each of therings 46 and 41, by its ability to move about freely in its associatedrecess, serves as a shiftable backing for the vanes 22, 22, the saidrings 46 and 41 changing their positions in the respective recesses asthe eccentricity between the rotor l8 and the surrounding ring 23 isincreased or decreased, as the case may be, and in the operation of thepump. Whatever the pumping position may be, said rings 48 and 41maintain their peripheral contact with the inner edges of the vanes 22,22 and thus insure the vanes contact by the outer edges with the innerperiphery of the modulating ring 23.

In Fig. 2 the ring '23 is shown in its position of maximum eccentricity,relative to the rotor l8, its movement to this position (of maximumpumping action by the vanes 22, 22) being obtained by the thrustthereupon of a suitable spring 48 disposed within an opening or socket50 provided in the peripheral wall of the bore 15. One end of thisspring engages the deepest or base portion of the opening or socket 59and the other end of the spring is seated within a recess 5| provided inthe peripheral portion of the ring 23 opposite the socket 50. Thepressure of the spring 48 against the ring 23 biases the ring about itspivot rib 28 to the end that the lower portion of the ring (as depictedin Fig. 2) will normally approach contacting relation with the lowerportion of the bore [5. It is to be understood that the spring 48virtually floats between the ring 23 and the base portion of the opening58 thereby to provide a movable direction of spring thrust. Should thering 28, with its pump inactive or at rest, be in any way displacedunder pressure from the spring 48, from the position of Fig. 2, so asnot to sit perfectly on its edge 29 in its angular indentation 38, it isevident that upon starting up of the rotor's rotation in the directionof the arrow 42, the ring 23 will be immediately and automatically movedto correct seating position due to the pressure of fluid against theinterior surface of the ring in the zone of said seating, which causesthe edge 29 to bottom in the indentation 30. If fluid in excess ofoutput requirements is being delivered to the pump, the resultingincrease of fluid pressure in the wedge shaped zone 49 between rotor andmodulator ring becomes immediately effective against the rings surfacein said zone to move said ring, against the pressure of the spring 48,towards a less eccentric position relative to rotor l8 whichautomatically reduces the pumping action of the vanes 22, 22

' to a point in keeping with the output requirements. Thus, under allconditions, the pump will automatically adjust itself to deliver fluidunder pressure only in the amounts required by the device or deviceswhich it is supplying.

Referring particularly to Figs. 1, 2, 3, and 4,

"the-hub portion 5| of the-port-containing member 21 is received within:an axial bore 52pm.- .vided in the end cap H. The one end of the shaftl6 projects forwardly of the member "27 and into the bore 52 for thepurpose of providing a means upon which an'o'il seal 53 may be placedwithin the-end cap ll thereby to prevent the egress of fluid along theshaft "l6 and out through the axialopening of the-end cap H. A similaroil-seal 53"is"provided about the other end of'the shaft l6 and withinan'ap'erture '54 provided in the rear wall ofthe housing in. This oilseal 53 will prevent the egress of oilalong the shaft andout'through'the rear end portionof the housing l0.

Provided-in the peripheral portion-of the housing I0 is a pair of spacedapertures 55 and 55 which communicate respectively witha pair oflongitudinally disposed passageways Hand '58 which are formed in'the'housing Hl'thus to communicate with'the end" cap H. Referringparticularly to Figs. 1, 3, and-4, the end cap I l is provided withraised portions 59 and 66 which contain'passageways 6! and '62respectively. When the end cap II is placed'in its proper position overthe housing It the passageways 6| and 62 are disposed in register overthe passageways 51 and 58, respectively, for the'purpose of placingthese latter passageways in communication with the passageways '36 and35 respectively of the port-containing member 21. Referring particularlyto Fig. 4, it is to be understood that the passageway 58 is adaptedto-deliver oil tothe intake or low pressureside of the rotor through thepassageway Brand the oil passageway 35 the latter of which isformed inthe port-containing member 2'1. It isa'lso to be-understood thatthe oilwhich is forced under pressurethrough'the outlet passageway 36 of themember 2! will find its way out of the housing 10 by way-of-thepassageway GI and the passageways 5 and 55.

In the event that it is desired-to rotate the shaft I6 in the directionof the arrow ll as disclosed in Fig. 3, it is merely necessary in thepresent device to reverse the position of'the ring 23 as shown inFigp2so that the-rib member 28 will be positioned within-the-cleft 3lrather than within the cleft 30. This will, of course, not affect theeificiency of the pumping unit as it will merely permit the ring 23 to.function within the cleft 3| in exactly'the same manner as itfunctioned within the cleft '30. When this change is made, however, someprovision must be made whereby the inletandoutlet ports may be shiftedso'that they 'mayproperly conduct oil to and from the pumping'unit. Inorderto accomplish this objective, the present port-containing member2'! has been so designed'that it may be shifted from the position shownin Fig, 4 to the position shown in Fig. 3. This change involves merelyturning the member '21 within the bore 34 of the end plate I I until, itis disposed in the position as disclosed in Fig. 3. It is to beunderstood that when the member 21 is so shifted there is a completereversal of the functions of the oil intake and'outtake passages whichare provided within the housing H). In other words, whenever the plate21 is so shifted the intake aperture 31 provided in the member 21 ismoved from register with the passageway 62 ofthe end plate H intoregister with the passageway 6| of the end plate, and by the same tokenthe outlet passage 38 is shifted from register with' passageway 61' ofthe end plate ll into register with the'passageway 62'of theen'd plate."There- 6 fore, to reverse the present sum-ping iuiit come pletely oneneed only *shift 'the nembr '21 "as 'hereinabove described, -'-'reversethe position of the ring 23, and switch @thefiu'id intake and inletlilies-which would hermally be attached to the bores "55 and 5'5of-thehous'ing l-D.

As shown particularly 'ih Fig. '1, "the members 21 and 'll are providedwith dowel pin apertures 63 and54, respectively, "for the purpose ofreceiving a 'clowel pin 65 which'functions to place the member 21 in itsproper position relativeto the rotor. As maybenot'ed "in 'Fig. '7, themember 2'1 is provided' with' a second dowel pin hole 66 which may 'beutilized whenever the member-21 is-shiftedintothe position as in-(heated in Fig. f3 thereby {to 'pern'iit the dowel pin 65to align thedowel "pin hole 66 with the dowel-pin hole 63 of the-member -I I. Fromthis it will be understood-that the member 21 may be accuratelypositioned-within'the end cap II for either "clockwise orcounterclockwise rotation of theshaft l6.

Referring p'articularlyto Figs? and 4, it is to be understood that asthe port-containing memher 21 is shifted s'lidingly in a-'counterclockwise direction about theshaft IGthearea ofapplied thrustoutwardly against the ring 23 will shift from zone 49*"to "a"point-,"closer to the rib 28. By so-shifting the direction-of thrusttheoil will be required to -produce a=greater force upon the ring 23 inorderto shift'the'sameto its position of minimum eccentricity. "By thesame token, it isto be understood that if the'memher were to beshiftedin a clockwise-direction, as vieweclin Fig. 4, 'the'oil wouldfberequired to produce a lesser force-upon the ring 23 in order to shiftthe same to its position of minimumeccentricity. Thisisfor thereason-that theeifective-lever distance' from thespring 48*to thefulcrum point 29 ofthe ring23 remains substantially constant while theeffective lever distance from the area of applied thrust-against thering to the fulcrum point 29 is decreased or increased, depending uponwhether *the member 21 is rotated in a counterclockwise 'or a clockwisedirection From theabove it is to be'und'erstood that by so shifting themember'il-ab'out the shaft IS the effective-pressure of the oil iiowingout of the pump casing will be increased as the member is turn'ed'inacounterclockwisedirection and will be-decreasedasit is turned in aclockwise direction. However, when the member 2! is positioned withinthe pumpunit as illustrated in Fig. 3, it must be adjusted in a mannerjust opposite to that as above described in order to effect the sameresults. But inorder to so alter the positionof the'memberl"!some'adjusting' means required. The present invention contemplates theprovision of such means.

'It'willbe-understood that whenever it is desired *toincor'porate thehereiuabove noted adjusting means within the present. oil pump, thedowel pin 55 must be omitted'from the assembly. In lieu of thisdowel'pin'there is provided a worm gear 61 which isjournaled withi'n'theend plate H. The inner end of the worm gear 61' may be formed with abearing member 68 ad'apted to be received within a cylindricalseat 69formed in the bottom portion ofa bore 10 which is adapted toreceive'thelarge cylindflcaiehdpoition H of the worm 61. The outerend ofthe member H projects out ofthebore 10 and has formed thereon a; headmember "TI-the function of which. is to provide meahswheiebfthwornrmalf'brotated.

A screw 13 is threaded into the plate II for the purpose of projectinginto an annular groove 13' formed about the member I I Thus, the worm isprevented from shifting lengthwise of itself. A set screw 14, alsothreaded into the plate II, is adapted to engage the member H thereby tolock the same in any desired position.

The worm 61 is adapted to mesh with gear teeth 15 provided on the outerperiphery of the member 21. Referring particularly to Fig. '1, it willbe seen that the teeth 15 are disposed about the peripheral portions ofthe member 21 for the purpose of providing means whereby the member 2'!maybe rotatably adjusted whether it be in the position disclosed in Fig.3 or in Fig. 4. From this it is to be understood that the rotation ofthe worm 61 will be effective to rotate the member 21 within the bore 34of the end plate to the end that the pressure of the oil flowing fromthe pump may be varied. It will occur to those skilled in the art thatother means could be provided for adjusting the member 21 about theshaft ii. For example, link and crank elements could be substituted inlieu of the worm and wheel expedient herein used. However, suchmodifications all come within the scope of the present invention.

From the above it is to be understood that the present inventionprovides a novel and extremely efficient pump which is adapted to beassembled in two different ways thereby to produce a pump which willrotate in either of two directions.

Furthermore, this pump is so constructed that by a very simplemanipulation the unit may be effective to produce various pressures uponthe oil which is forced therethrough.

We claim:

1. In a variable delivery fluid pump, an outer housing providing ahollow chamber and fluid intake and delivery connections, a rotor havingradially slidable vanes and rotatable in said chamber, a ring-likemember pivotally mounted at one side thereof within said chamber anddisposed so as to surround said rotor and cooperating by its innersurface with said vanes to produce the pumping action, yieldable meansbiasing said member about its pivotal mounting to eccentric positionrelative to said rotor for maximum pumping action by said vanes, saidintake and delivery connections being so disposed I relative to saidring-like member as to cooperate with said rotor in producing a pumpingpressure acting on an inner surface area of said ringlike member betweensaid pivotal mounting and said biasing means, in a direction to movesaid ring in opposition to said biasing means toward concentric ornon-pumping position to minimize the pumping action, means adjustable toalter the position on said inner surface of said ringlike member atwhich said pumping pressure is applied, and means extending out of saidhousing for effecting the adjustment of said last named means.

2. In a reversible variable delivery fluid pump, an outer housingproviding a hollow chamber and fluid intake and delivery connections, arotor having radially slidable vanes and rotatable in said chamber, aring-like member pivotally mounted at one side thereof within saidchamber and disposed so as to surround said rotor and cooperating by itsinner surface with said vanes to produce the pumping action, yieldablemeans biasing said member about its pivotal mounting to eccentricposition relative to said rotor for maximum pumping action by saidvanes, said biasing means thrusting said member to move pivotally in thesame general direction as the direction of rotation of said rotor and inopposition to a tendency of the member to pivot in the oppositedirection responsive to pumping pressure acting on an inner surface areaof said member between said pivotal mounting and said biasing means formodulating the pumping pressure, means provided in said housing so thatthe relative positions of said pivotal mounting and said biasing meansmay be reversed whenever the direction of rotation of said rotor is tobe reversed thereby to permit said biasing means to urge said memberabout its pivotal mounting in the same general direction as thedirection of rotor rotation in either of said positions of the pivotalmounting, means adjustably disposed within said housing and havingspaced intake and delivery ports therein connecting said intake anddelivery connections with said chamber, and means for adjusting saidlast named means within said housing so that a portion of its deliveryport may be selectively positioned at various locations between saidbiasing means and said pivotal mounting in either of said positions ofthe pivotal mounting of the member.

3. In a reversible variable delivery fluid pump, an outer housingproviding a hollow chamber and fluid intake and delivery connections, amoduiator ring, said housing and said modulator ring having meanscooperating to define a pair of spaced selectively usable fulcrum pointswith respect to which the modulator ring is adapted to be rockablymounted in said chamber to rock about either selective one of said pairof spaced fulcrum points, a rotor having radially slidable vanes andbeing rotatable in said ring in either direction so as to produce thepumping action by cooperation of said vanes with the interior surface ofsaid ring, means movably disposed within said housing and having spacedintake and delivery ports therein connecting said intake and deliveryconnections with said chamber, means for maintaining said last mentionedmeans in a selective one of two positions to which it may be movedwithin said housing depending upon about which of the selective fulcrumpoints the modulator ring is rockable, a portion of said ring's interiorsurface in the zone of said delivery port being acted on by the pumpingpressure in a direction tending to shift said ring toward a positionconcentric with said rotor to thereby minimize the pumping pressure, andspring means acting on said ring in opposition to the pumping pressureand tending to rock said ring to a position eccentric to said rotor forincreasing the pumping pressure.

4. In a variable delivery fluid pump, an outer housing providing ahollow chamber and fluid intake and delivery connections, a pair offulcrum means disposed substantially at diametrically opposed pointsrelative to each other at the inner peripheral portion of said chamber,a ring-like member having a pivotal element formed on the peripherythereof, said ring-like member being assembled into said chamber withits pivotal element in engagement with a selective one 'or" said fulcrummeans, a rotor having radially slidable vanes and the rotor beingselectively reversely rotatable in said ring-like member so that ineither direction of rotation said vanes will produce the pumping action,and spring means disposed substantially degrees out of phase with eachof said fulcrum means for urging said ring-like member into eccentricposition relative to said rotor'f -or gagement of the pivotal elementwith either selective one of said fulcrum means conformable to thedirection of rotation of said rotor to thereby enable the ring-likemember to rock about either fulcrum in the general respective directionof rotation of the rotor.

5. ma variable delivery fluid pump, a housing providing a chamber andhaving fluid intake and delivery passages, a modulator movably mountedin said chamber and having'a circular pump chamber therein, aselectively reversibly rotatable rotor having pumping means engaging thewall defining saidpumping chamber within the modulator to effect fluiddisplace ment upon rotation of the rotor, the modulator being movable insaidhousing chamber to vary the relationship of the pumping chamber wallcccentrically with respect to the'roto'r for"va1i able fluiddisplacement by the pumping means, a member assembled within saidhousing between the modulator and rotor and saidfluid intake anddelivery passages and having spaced intake and delivery ports thereinfor connecting said intake and delivery passages with said pump chamher,said member being movable within'the hous ing and relative to said rotorfor adjusting the relative positions of said intake and delivery portsto accommodate the respective reverse pumping "rotations of the rotor,and an element having engagement with the housing and with said memherfor retaining'the latter in any position to which "said member may bemoved within the housing for proper relationship of the intake anddelivery ports with respect to the direction of rotation of the rotor.

6. A pump construction as defined in claim 5 wherein said elementcomprises a dowel and the housing and said member have respective dowelsockets for inter-engagement therein of the dowel.

'7. A pump construction as defined in claim 5 wherein saidelementcomprises a manually operable screwhaving a manipulating portionexternally of the housing.

' 8. In a reversible variable delivery fluid pump, an outer housingproviding a hollow chamber and fluid intake and delivery connections, aring-like modulator member pivotally mounted at one side thereof Withinsaid chamber, a rotor having radially slidable vanes and rotatablewithin said ringlike member to produce the pumping action, means biasingsaid member about its pivotal mounting to eccentric position relative tosaid rotor for maximum pumping action'by said vanes, the thrust of saidbiasing means on said member being in the same general direction'as thedirection of rotation of said rotor, said biasing means being yieldableto enable pivoting of said member in opposition to said thrust forvarying the pump capacity responsive to pumping pressure acting on aninner surface of said member between said pivotal mounting and saidbiasing means, means provided in said housing so that the relativepositions of said pivotal mounting and said biasing means may bereversed whenever the direction of rotation of said rotor is to bereversed thereby to permit said biasing means to urge said member aboutits pivotal mounting in the same general direction as" the reverseddirection of rotor roanoameans' disposed within said housing formovement within and relative to the housing and having spaced intake anddelivery ports therein connecting said intake and s ctiv'e fulcrummeans" enabling reversal of the ring-like member for'erv' portion ofsaid modulator 'memberfor'se delivery connections with said chamber, and

means for securing said last 'namedme'aris' in a selective one of'twopositions to 'wh'ich it is moved within said housing so thatat'leasta portion of its delivery port may be positioned substantially betweensaid" biasing mea11s""and the "pivotal mounting in either of saidpivotal""mounting positions of said member to accommodate said reversalsof rotation'of the rotor.

91111 a reversible variable delivery fluid pump, an outer housingproviding a hollow chamber and fluid intake and deliveryconnections; a"pair" of fulcrum means disposed substantially at diametrically opposedpoints relative" to eachbther' at theinner peripheralportion ofsaidchambe'r, a ring-like modulator" member movablymounted' in saidchamber, a rotor or smaller diameter than the" inner diameter'of saidmodulator member and rotatable within themodulator 'm'ember'an'd having"radially movable "elements cooperating with'the modulator member toproduce a pu p: in'g action'upon rotation of the rotor in'th moa latormember, means'dis'p'o'sed' upon the outer portiorr' of said modulatormember *for selected engagemenhwith one or 'said pair of fulcrum meansto thereby provide with" either of said fulcrum'means' a pivotalmounting" for said'modu lator member for varying pump displaement'byswiii'ging of the modulatonmember about the selected'pivot, meansdisposed substantially degrees out of phase "with each of "Said fulcrummeans for urgin said modulator member 'to' swing about the' selected oneof said'fulc'rum means into an "eccentric position relative to saidrotor "for maximum pumping action by said a: dially movable elements,and "means movably disposed within said housingfor 'efiecting operativeconnection between said intake and delivery conmotions in either of theselective pivotal mount ings of the modulator member; said movablydisposed means having intake and delivery ports connectedwith"'said'intake and delivery connec tions'and being adapted to beselectively moved and position'ed'within said housing complemenf tary tothe respective pivotal mountings of the modulator member tocontrol theapplication of pumping pressure'to an' inner surfac area of saidmodulator memberloc'ated between the selected'one of said fulcrum'meansengaged by said means on the outer portion of the" fulcrum member andsaid biasing means for moving the modulator member towards concentric ornon pumping position'r'elative to the rotor and in opposition to saidbiasing means for reducing the pumping'action of sai'delements.

' 10'. In a reversible'variabledelivery fluid pump, an'oute'rhousing'providing ahollow chamber and fluid intake and deliveryconnections, a pairof fulcrum means disposed substantially atdiametrically opposed points relative to eachother at the innerperipheral portion of said chamber, a ring-like modulator member movablymounted in'said chambena rotor of smaller diameter than the" innerdiameter of said'modulator member and rotatable'within 'themodulatormember and having radially movable elements cooperating with" themodulator member'to produce'a pumping 'action'upon rotation of the rotorin the modulator member, means'disposedupon the outer ted ng e e w th"one f sa d a rflo rul r mesns m therebyprdvide with either-bfsa'i'diulcrummeans a pivotal mounting for said modulator member forvarying pump displacement by swinging of the modulator member about theselected pivot, means disposed substantially 90 degrees out of phasewith each of said fulcrum means for urging said modulator member to swinabout the selected one of said fulcrum means into an eccentric positionrelative to said rotor for maximum pumping action by said radiallymovable elements, means movably disposed within said housing foreffecting operative connection between said intake and deliveryconnections in either of the selective pivotal mountings of themodulator member, said movably disposed means having spaced intake anddelivery ports therein for connecting said intake and deliveryconnections with the interior of the modu lator member, and means forsecuring said movably disposed means in a selective one of two positionsinto which it may be moved within said housing so that at least aportion of its delivery port may be positioned substantially betweensaid biasing means and the selected fulcrum means that is engagedselectively by said means disposed on the outer portion of the modulatormember and the inner peripheral wall of the modulator member therebysubjected to pump pressure in opposition to said biasing means forautomatically varying the pump pressure responsive to increase of pumppressure beyond a predetermined value.

11. In a reversible variable delivery fluid pump, an outer housingproviding a hollow chamber and fluid intake and delivery connections, apair of fulcrum means disposed substantially at diametrically opposedpoints relative to each other within said chamber, a ring-like modulatormember movably mounted in said chamber, a rotor of smaller diameter thanthe inner diameter of said modulator member and rotatable within themodulator member and having radially movable elements cooperatin withthe inner peripheral wall defining the modulator member to produce apumping action upon rotation of the rotor in the modulator member, meansdisposed upon the outer portion of said modulator member for selectedengagement with one of said pair of fulcrum means to thereby providewith either of said fulcrum means a pivotal mounting for said modulatormember for varying pump displacement by swinging of the modulator memberabout the selected pivot, means disposed substantially 90 degrees out ofphase with each of said fulcrum means for urging said modulator memberto swing about the selected one of said fulcrum means into an eccentricposition relative to said rotor for maximum pumping action by saidradially movable elements, and means movably disposed within saidhousing for effectiv operative connection between said intake anddelivery connection in either of the selective pivotal mountings of themodulator member, said movably disposed means having two differentselective positions of assembly within the housing correspondingenerally to the respective reverse mountin positions of the modulatormember so that in either of said reverse mounting positions of themodulator member at least a portion of the delivery port of said movablydisposed means will be positioned substantially between said biasingmeans and the respective engaged fulcrum means.

12. In a variable delivery fluid pump, an outer housing providing ahollow chamber and fiuid intake and delivery connections, a ring-likemodulator member within said chamber and having pivotal connections atone side of the member for rocking thereof within the chamber, a rotorrotatable on a fixed axis and disposed within said modulator member andhaving radially movable elements cooperating with the inner surface ofthe modulator member to produce a pumping action, means biasing saidmodulator member about its pivotal mounting to eccentric positionrelative to said rotor for attaining maximum pumping action by saidelements, said biasing means being yieldable responsive to internalpumping pressure within the modulator member to permit movement of themodulator member to positions of less eccentricity with respect to therotor in order to vary the pump displacement, and means for connectingsaid fluid intake and delivery connections with the interior of themodulator member, said last mentioned means being adjustable relative tothe modulator member to alter the effective fluid pressure upon themodulator ring to shift it in opposition to said biasing means duringrotation of the rotor.

13. In a variable delivery fluid pump, an outer housing providing ahollow chamber and fluid intake and delivery connections, a ring-likemodulator member within said chamber and having pivotal connections atone side of the member for rocking thereof within the chamber, a rotorrotatable on a fixed axis and disposed within said modulator member andhaving radially movable elements cooperating with the inner surface ofthe modulator member to produce a pumping action, means biasing saidmodulator member about its pivotal mounting to eccentric positionrelative to said rotor for attaining maximum pumping action by saidelements, said biasing means being yieldable responsive to internalpumping pressure within the modulator member to permit movement of themodulator member to positions of less eccentricity with respect to therotor in order to vary the pump displacement, means for connecting saidfluid intake and delivery connections with the interior of the modulatormember, and means for a fiusting and maintaining said last mentionedmeans relative to said housing in predetermined respective positions ofsaid ports relative to said modulator member.

WARREN H. DE LANCEY. EDWIN E. VINCENT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

